1. Field of the Invention
The present invention relates to the field of temporarily installed guard rail stanchions and, more particularly, to clamp-on type guard rail stancions.
2. Description of the Prior Art
As floors are added in multi-floor building construction, workmen are required to work on the floors before walls are installed. To prevent falling of workmen, material and equipment, installation of temporary guard rails around floor perimeters and cut-outs for elevators, stairs, etc., it is now generally mandatory to comply with state and Federal safety regulations.
Several different types of temporary guard rail stanchions or supports have been disclosed. These types include stanchions which require receiving structure to be built into the floor, stanchions which require bolting to floor structure such as wooden beams, and stanchions which clamp on edges of the floor. An example of the first type is Dickey, U.S. Pat. No. 3,584,839; an example of the second type is Gilbert et al., U.S. Pat. No. 3,425,509; and examples of the more common, clamp-on type are Squire, U.S. Pat. No. 3,084,759; Bourn et al., U.S. Pat. No. 3,480,257; Warren, U.S. Pat. No. 3,747,898 and Smith, U.S. Pat. No. 3,841,609.
A number of problems are however, associated with heretofore available or disclosed temporarily installed guard rail stanchions. Stanchion receiving portions required to be built into the floors may be forgotten, damaged or blocked and the stanchions to be received often cannot be properly installed. Similarily mounting holes required for mounting some types of stanchions may be missing or misaligned. Stanchions requiring in-place bolting to wooden members may encounter floors with no wooden members to which the stanchions may be bolted. Even the more generally used clamp-on stanchions present problems. Some types are relatively complex and costly, and are easily damaged, after which their safety is impaired. Others employ small removable parts which may easily be lost, thereby rendering the clamp inoperable or unsafe. Many types require an installer to reach far over the edge to position or actuate the clamp and are thus dangerous to install. All known types are adaptable only for clamping to generally parallel opposing horizontal surfaces. On many occasions, however, the floor edge may be formed of an "I" beam or "U" channel having only parallel vertical clamping surfaces. Also, no known type provides a reliable visual indication when a predetermined clamping force, sufficient to provide safe and secure clamping, has been applied.
These and other problems are compounded by a necessity for removing the entire stanchion assembly, including the mounting portion, in order to provide clearance for receiving large equipment and some types of material. Not only does such removal and reinstallation give rise to the great possibility of lost parts and unsafe installations, but it is also time consuming and thus expensive.
There is known to applicant no types of temporary guard rail stanchions which have post portions which may be readily removed from the mounting portions and reinstalled without disturbing the clamping or securing portions which provide a visual indication of a predetermined clamping force or which may be clamped to vertical surfaces.